Metadata is generally defined as “data about data”. In the context of audio visual (AV) content, the term metadata refers to descriptive data about that content, such as duration, programme title and synopsis. Once AV content has been created and information about the programme has been captured, the content is then available for publication by a content publisher. This could be, for example, as part of a broadcast service or as a publication on the Internet. The metadata editing process takes raw information from the content creation and publishing processes and edits this into a form that is suitable for representing the content to the end consumer.
Segmentation refers to the ability to define, access and manipulate temporal locations or intervals (segments) within a piece of AV content. By associating metadata with segments, it is possible to restructure and re-purpose an input AV stream to generate alternative consumption and navigation modes. Such modes could include, for example, a summary of the content with highlights, or a set of bookmarks that point to “topic headings” within the stream. Such segmentation metadata can be provided by service providers or broadcasters as a value-added feature and/or generated by viewers themselves.